cygnusx1 Posted September 22, 2011 Share Posted September 22, 2011 (edited) I ordered the performance shoes from MSA and installed them on the 77 I am working on. I used the inboard plugs to access the adjusters, to tighten up the shoes until they began to drag in the drums. I applied the brakes, pulled on the handbrake several times and re-checked the adjusters. Test driving the car, the brakes feel good overall. The problem is that the handbrake barely holds the car on any slight incline. I checked the handbrake cable tension and it starts to move the mechanical shoe levers after the first click at the handle. I can pull the handle almost vertical with very little parking brake action. Could this indicate that the shoes are not contacting the drum face properly? The drums are in spec. MSA had called me after I placed the parts order to make sure I ordered/wanted 77 shoes because they said there were differences from year to year. Maybe they sent the wrong shoes? Any ideas? After a spirited drive, the rotors are coming back around 300F and the drums are reading about 120F. I just feel if they are so bad at being handbrakes, they might not be doing much with the pedal brakes either. Edited September 22, 2011 by cygnusx1 Quote Link to comment Share on other sites More sharing options...
NewZed Posted September 22, 2011 Share Posted September 22, 2011 The shoes are different. They changed from a single piston floating wheel cylinder to the dual piston type in 78, so the contact points on the shoes are different, if I recall. Maybe you don't have a 77 setup. I put a 78 rear suspension on my 76 (because I had it and it was in better condition than what I had on the 76), so have seen both. One possibility, in your case. Also, I noticed when I put new shoes in mine that the shoes seemed to be manufactured for a larger diameter drum. Only the forward and trailing edges were actually contacting the drum. Brake pedal travel varied for a few thousand miles until they wore in (when the pedal travel got high I would crank on the parking brake to shorten it. Did that quite a few times). Maybe the manufacturers expanded the shoe diameter to match the average drum size after turning? Just a couple of thoughts... Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 22, 2011 Author Share Posted September 22, 2011 The cylinders have dual pistons on this car but that does not mean they are correct I suppose. I'll check the wear marks on the shoes. Quote Link to comment Share on other sites More sharing options...
NewZed Posted September 22, 2011 Share Posted September 22, 2011 Just realized that 77 might be the year of the change. I checked an auto store site and that seems to be the case. So 76 was the last year of the floating cylinder. 77 should have the duals. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 22, 2011 Author Share Posted September 22, 2011 I will take the brakes apart again today for the third time....I'll try to measure the installed diameter of the shoes with the drums off, to see if it comes close to the measured ID of the drum. After some research it seems that the shoes changed width from 76 to 77 but I think the drum diameters remained the same. Quote Link to comment Share on other sites More sharing options...
johnc Posted September 22, 2011 Share Posted September 22, 2011 Put some miles on the brakes before doing anything else. Check it again after a couple hundred miles. Also try a hard panic stop to see which tire/end locks up first. And expect to adjust the rears a few times during that 200 mile bed in. 1 Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 23, 2011 Author Share Posted September 23, 2011 Trouble is, it's not my car and I don't want to let it go unless I know it's working. I did panic stops and the front lock up. No sign of locking from the rear. I can try to lock up all four wheels but I am afraid of doing this on the street and/or flat spotting tires. I will just inform the owner and keep in touch with him I suppose. Quote Link to comment Share on other sites More sharing options...
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